Posted: Apr 7th 2010, 05:50 PM
Sorry, I guess I should have said they don't work on my M-15 with the proprietary bolt. You probably already know this, but the way to check the gas rings is to set the bolt carrier with the bolt face down on a flat surface with the bolt extended. If the bolt stays extended under its own weight you are good to go. If the bolt collapses into the carrier, the rings need to be replaced.
The inside of my M-15 carrier is larger than the inside diameter on my Bushmaster carrier and
RRA carriers so brand new McFarland rings wont work in it. The ArmaLite bolt will slide in and out with almost no resistance with the McFarland rings installed (I tried 3 different rings, still in plastic) . Three piece MIL-Spec rings work just fine so that is what I use in the M-15. If someone has not liked them on one of their guns they have probably had the same problem I have.
Like I said above, I use them on all my guns other than the ArmaLite and they last longer than Mil-Spec rings. I usually buy them 5 at a time and I try to keep standard 3 piece rings in my repair kit as well. I was surprised that they wouldn't work in the M-15.
